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PRACTICAL ORGANIC CHEMISTRY

PREPARATION 20.

CHg.NHa.HCl
Q-lycocoll Ester Hydro chloride,   \

CO.OC2H-

Klages, Ber., 1903, 36, 1506, Hantzsch and Silberrad,
1900, 33, 70.

250 c.c, formaldehyde solution (40 per cent.).
90 grams ammonium chloride (powdered).
1 10          potassium cyanide (in 200 c.c. water).
63 c.c. glacial acetic acid.    "

The first part of the process consists in the preparation of
methyleneamino-acetonitrile.

The formaldehyde and ammonium chloride are mixed in a
wide-necked glass jar cooled in a freezing mixture and
stirred by means of a stirrer as shown in Fig. 64. When the
temperature falls to 5 the potassium cyanide solution is slowly
run in from a tap-funnel during three hours, the temperature
being maintained below 10. When half the cyanide solution
has been added the ammonium chloride will have com-
pletely dissolved. Whilst the second half of the solution is
being added, 63 c.c. of glacial acetic acid are dropped in from
another tap-funnel at about the same rate, whilst the tempera-
ture is kept below 15. As soon as the acetic acid is
added a white 'crystalline substance begins to separate and
gradually fills the liquid. The stirring is continued for another
hour after the solutioris have been added. The crystalline mass is
filtered, washed with water and dried. The yield is 60  70 grams.
Methyleneamino-acetonitrile melts at 1 29. 1 1 m ay be recrystallised
from alcohol, but is usually pure enough for further treatment.
On hydrolysis in presence of alcohol it breaks up into glycocoll
ester hydrochloride, ammonium chloride and formaldehyde.
CH2:N. CH2CN + 2H2O + C2H5OH -I- HC1 = (HCl)NHa, CH0. COOC,HB
+ NH4C1 + CH20.
Twenty-five grams methyleneamino-acetonitrile are added to
170 c.c. of absolute alcohol previously saturated in the cold
with hydrogen chloride.